A 6-year-old boy was killed and his mother and 9-year-old sister were injured Sunday when their car flipped, landing upside down in a drainage ditch in east Harris County.

Zulma Sevilla lost control of her black 1997 Toyota Corolla around 7:50 a.m. and crossed the center line in the 16200 block of De Zavalla in east Harris County. Her vehicle slid into the roadside ditch, hit a concrete retention area and flipped, accident investigators said.

Carlos Chavez, 6, was flown to Memorial Hermann Hospital, where he died from his injuries. Sevilla and her 9-year-old daughter were taken by ambulance to the same hospital, where they are listed in serious but stable condition.

The Harris County sheriff's traffic enforcement division continues to investigate the accident and declined to provide other details.